PW80s will run on piss and vinegar. Put 20:1 pre-mix in the tank, disconnect the hose from the pump to the carb on the carb side, plug the carb nipple (electrical tape would do, a length of hose with a screw in it, anything to temporarily keep the carb from sucking air in the hole), run the engine. You should get
a stead drip of oil, I don't remember the PW80 specs, but the KE100 is supposed to be 3 ml per 3 minutes at idle. It might need to be primed which I forget what the procedure is since I've never had to do it. I hope someone remembers.
But I'd expect within 5 minutes of running at idle it should have primed itself if there's oil in the tank.
3ml is roughly half a teaspoon.